Quantification of dendritic and axonal growth after injury to the auditory system of the adult cricket Gryllus bimaculatus
Dendrite and axon growth and branching during development are regulated by a complex set of intracellular and external signals. However, the cues that maintain or influence adult neuronal morphology are less well understood. Injury and deafferentation tend to have negative effects on adult nervous...
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| Format: | Article |
| Language: | English |
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Frontiers Media S.A.
2013-08-01
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| Series: | Frontiers in Physiology |
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| Online Access: | http://journal.frontiersin.org/Journal/10.3389/fphys.2012.00367/full |
| _version_ | 1818275250610110464 |
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| author | Alexandra ePfister Amy eJohnson Olaf eEllers Hadley Wilson Horch |
| author_facet | Alexandra ePfister Amy eJohnson Olaf eEllers Hadley Wilson Horch |
| author_sort | Alexandra ePfister |
| collection | DOAJ |
| description | Dendrite and axon growth and branching during development are regulated by a complex set of intracellular and external signals. However, the cues that maintain or influence adult neuronal morphology are less well understood. Injury and deafferentation tend to have negative effects on adult nervous systems. An interesting example of injury-induced compensatory growth is seen in the cricket, Gryllus bimaculatus. After unilateral loss of an ear in the adult cricket, auditory neurons within the central nervous system sprout to compensate for the injury. Specifically, after being deafferented, ascending neurons (AN-1 and AN-2) send dendrites across the midline of the prothoracic ganglion where they receive input from auditory afferents that project through the contralateral auditory nerve (N5). Deafferentation also triggers contralateral N5 axonal growth. In this study, we quantified AN dendritic and N5 axonal growth at 30 hours, as well as at 3, 5, 7, 14 and 20 days after deafferentation in adult crickets. Significant differences in the rates of dendritic growth between males and females were noted. In females, dendritic growth rates were non-linear; a rapid burst of dendritic extension in the first few days was followed by a plateau reached at 3 days after deafferentation. In males, however, dendritic growth rates were linear, with dendrites growing steadily over time and reaching lengths, on average, twice as long as in females. On the other hand, rates of N5 axonal growth showed no significant sexual dimorphism and were linear. Within each animal, the growth rates of dendrites and axons were not correlated, indicating that independent factors likely influence dendritic and axonal growth in response to injury in this system. Our findings provide a basis for future study of the cellular features that allow differing dendrite and axon growth patterns as well as sexually dimorphic dendritic growth in response to deafferentation. |
| first_indexed | 2024-12-12T22:26:46Z |
| format | Article |
| id | doaj.art-6ac57dca60404ef9b71486ae60d8094c |
| institution | Directory Open Access Journal |
| issn | 1664-042X |
| language | English |
| last_indexed | 2024-12-12T22:26:46Z |
| publishDate | 2013-08-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Physiology |
| spelling | doaj.art-6ac57dca60404ef9b71486ae60d8094c2022-12-22T00:09:43ZengFrontiers Media S.A.Frontiers in Physiology1664-042X2013-08-01310.3389/fphys.2012.0036730126Quantification of dendritic and axonal growth after injury to the auditory system of the adult cricket Gryllus bimaculatusAlexandra ePfister0Amy eJohnson1Olaf eEllers2Hadley Wilson Horch3American Museum of Natural HistoryBowdoin CollegeBowdoin CollegeBowdoin CollegeDendrite and axon growth and branching during development are regulated by a complex set of intracellular and external signals. However, the cues that maintain or influence adult neuronal morphology are less well understood. Injury and deafferentation tend to have negative effects on adult nervous systems. An interesting example of injury-induced compensatory growth is seen in the cricket, Gryllus bimaculatus. After unilateral loss of an ear in the adult cricket, auditory neurons within the central nervous system sprout to compensate for the injury. Specifically, after being deafferented, ascending neurons (AN-1 and AN-2) send dendrites across the midline of the prothoracic ganglion where they receive input from auditory afferents that project through the contralateral auditory nerve (N5). Deafferentation also triggers contralateral N5 axonal growth. In this study, we quantified AN dendritic and N5 axonal growth at 30 hours, as well as at 3, 5, 7, 14 and 20 days after deafferentation in adult crickets. Significant differences in the rates of dendritic growth between males and females were noted. In females, dendritic growth rates were non-linear; a rapid burst of dendritic extension in the first few days was followed by a plateau reached at 3 days after deafferentation. In males, however, dendritic growth rates were linear, with dendrites growing steadily over time and reaching lengths, on average, twice as long as in females. On the other hand, rates of N5 axonal growth showed no significant sexual dimorphism and were linear. Within each animal, the growth rates of dendrites and axons were not correlated, indicating that independent factors likely influence dendritic and axonal growth in response to injury in this system. Our findings provide a basis for future study of the cellular features that allow differing dendrite and axon growth patterns as well as sexually dimorphic dendritic growth in response to deafferentation.http://journal.frontiersin.org/Journal/10.3389/fphys.2012.00367/fullInvertebratesdeafferentationsexual dimorphismAnatomical plasticitymidline guidance |
| spellingShingle | Alexandra ePfister Amy eJohnson Olaf eEllers Hadley Wilson Horch Quantification of dendritic and axonal growth after injury to the auditory system of the adult cricket Gryllus bimaculatus Frontiers in Physiology Invertebrates deafferentation sexual dimorphism Anatomical plasticity midline guidance |
| title | Quantification of dendritic and axonal growth after injury to the auditory system of the adult cricket Gryllus bimaculatus |
| title_full | Quantification of dendritic and axonal growth after injury to the auditory system of the adult cricket Gryllus bimaculatus |
| title_fullStr | Quantification of dendritic and axonal growth after injury to the auditory system of the adult cricket Gryllus bimaculatus |
| title_full_unstemmed | Quantification of dendritic and axonal growth after injury to the auditory system of the adult cricket Gryllus bimaculatus |
| title_short | Quantification of dendritic and axonal growth after injury to the auditory system of the adult cricket Gryllus bimaculatus |
| title_sort | quantification of dendritic and axonal growth after injury to the auditory system of the adult cricket gryllus bimaculatus |
| topic | Invertebrates deafferentation sexual dimorphism Anatomical plasticity midline guidance |
| url | http://journal.frontiersin.org/Journal/10.3389/fphys.2012.00367/full |
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